HAVANA (CBS4) — Endurance athlete Diana Nyad is back in the water for her third attempt to swim from Cuba to Florida and set a world record at the age of 62.

Nyad set out from the Hemingway Marina in Havana on Friday evening and is swimming 100 miles through the Florida Straits to the Keys, possibly Islamorada.

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She has spent the day meeting with her support team, loading up on carbohydrates and loosening up. She’s hoping to take advantage of current favorable sea and weather conditions.

Shoulder pain, asthma and large ocean swells prevented her from completing the swim in August. She spent 29 hours in the water and was about halfway through the 103-mile journey when it ended. She said then that there would be no repeat.

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“Don’t listen to athletes when they say it’s over,” Nyad said Friday.

In her first attempt in 1978, at the age of 28, she quit after being in the water for 41 hours and 49 minutes due to strong currents and rough weather that banged her around in a shark cage.

This time, she’s trying it without a shark cage and if she completes it, she’ll be the first person to swim that stretch of ocean without a shark cage.

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